30 BOTANY OF MICHIGAN 



Carex retrorsa Schwein. Retrorse sedge. In marshy open or partially 

 shaded ground. Plentiful throughout. 



Carex inlumescens Rudge. Bladder sedge. In swampy, wet woods 

 and meadows. Frequent throughout. 



Carex lupulina Muhl. Hop sedge. Open marshy places. Frequent 

 throughout. 



Carex rostrata Stokes. Beaked sedge. Very wet open ground. Fre- 

 quent throughout. 



ARACEAE. Arum Family 



Arisaema IriphyUum (L.) Schott. Jack-in-t he-pulpit. Damp rich 

 shaded ground. Common throughout. 



Peltandra virginica (L.) Kunth. Green arrow arum. In shallow water 

 near Bay Cit3 r , Bay County. Plentiful. G. M. Bradford. 



LEMNACEAE. Duckweed Family 



Spirodela polyrhiza (I..) Schleid. Greater duckweed. Covering 

 shallow water in pools, ponds and coves throughout. Frequent and 

 often abundant. 



Lemna minor L. Lesser duckweed. Covering shallow stagnant water 

 and often on mud. Common throughout. 



* 

 ERIOCAULACEAE. Pipewort Family 



Eriocaulon articulatum (Huds.) Morong. Seven-angled pipewort. 

 Margin of Long Lake in Cheboygan County. Plentiful. Apparently 

 infrequent. 



XYRIDACEAE. Yellow-eyed Grass Family 



Xyris flexuosa Muhl. Slender yellow-eyed grass. In a very wet 

 marshy place near Au Sable, Iosco County. Apparently infrequent. 



PONTEDERIACEAE. Pickerel-weed Family 



Pontederia cordata L. Pickerel-weed. In shallow water on borders of 

 small lakes, in large ponds, and coves of streams, from Bay County to 

 Mackinaw City. Frequent throughout. 



Heteranthera dtibia (Jacq.) MacM. Water star-grass. Shallow water 

 near Bay City, Bay County. G. M. Bradford. 



JUNCACEAE. Rush Family 



J uncus bufonius L. Toad rush. Damp open ground. Common 

 throughout. 



Juncus tenuis Willd. Slender rush. Fields, roadsides, and along 

 paths. Common. 



